VendorMark said:

One practical note: write down what you did and when, before you need it.

This is where I part company with the consensus forming above. This treats a plausible mechanism as a demonstrated one. Plausible is where you start looking, not where you stop.

VendorMark said:

One practical note: write down what you did and when, before you need it.

That is right, and it stops being right at the edges. The general case is well behaved; the interesting cases in this thread are all at the boundary where the general case breaks.

VendorMark said:

One practical note: write down what you did and when, before you need it.

Thank you — that is the clearest version of this I have read, and I have read a lot of them.

Clinical perspective, offered as context rather than as advice. The useful move here is to separate what is established from what is widely repeated. Those two sets overlap less than the confident tone of most write-ups suggests, and the second set is where nearly all the disagreement on this board comes from.

Correct me if the detail matters more than I have assumed.

hyun_seoul said:

The useful move here is to separate what is established from what is widely repeated.

Adding a me-too, because a thread of one person's experience is not much use. Nothing to add that would improve it.